Railway track shunting apparatus



y 1937- B. E. OHAGAN 2,081,555

RAILWAY TRACK SHUNTING APPARATUS Original Filed Dec. 7, 1933 Fey, 2.

' INVENTOR Bernard E. OHagazz BY H] S A TTORNEY Patented May 25, 1937UNETED STATES PATENT OFFICE 2,081,555 RAILWAY TRACK SHUNTING APPARATUSApplication December '7, 1933, Serial No. 701,310 Renewed June 24, 193520 Claims.

My invention relates to railway track shunting apparatus of the typeinvolving means carried on a vehicle for facilitating the release of atrack relay by applying a potential to the rail 5 surface to disrupt theresistance film formed on such surface and thereby decrease the railcontact resistance.

The present invention is an improvement on apparatus disclosed andclaimed in an application for Letters Patent of the United States SerialNo. 644,180, filed by me on November 25, 1932, for Track shuntingapparatus.

One object of the present invention is the provision of means involvinga portion of the potential applying apparatus for indicating on thevehicle when a track relay has been effectively released.

I will describe three forms of apparatus embodying my invention, andwill then point out the novel features thereof in claims.

In the accompany drawing, Fig. l is a diagrammatic view showing one formof apparatus embodying my invention. Figs. 2 and 3 are views showingmodifications of a portion of the apparatus shown in Fig. 1 and alsoembodying my invention,

Similar reference characters refer to similar parts in each of theviews.

Referring first to Fig. 1, the reference characters i and I designatethe track rails of a stretch of railway track along which trafficnormally moves in the direction indicated by the arrow, which rails aredivided by insulated joints to form a track section C-D. This section is5 provided with a track circuit including a battery l6 connected acrossthe rails at one end of the section through a current-limiting impedancei7, and a direct current track relay P connected across the rails at theother end of the section. At the track relay end of the section thesecondary 2| of a transformer Q is also connected across the railsthrough a currentlimiting impedance l9. The primary 20 of transformer Qis connected through back contact I8 of relay P with a source ofalternating current, the terminals of which are designated X and Y. Itfollows that alternating current will be supplied to the rails ofsection C-D from the trackway source when and only when track relay P isopen.

The remaining apparatus illustrated in Fig. l is carried on a railvehicle. The reference character MG designates a motor generator setcomprising an alternating current generator G driven by a motor M whichreceives current from a battery B. A first transformer AI has a primarywinding 3 which is supplied with current from the generator G through acurrent-limiting reactor l3. This transformer is provided with twosecondary windings 4 and 5 having substan- 5 tially the same number ofturns. Winding 4 is connected across the two track rails l and I bymeans of suitable contactors 6 and 9, which may be contact shoes or maybe staggered wheels of the vehicle. Secondary 5 is similarly connectedacross the rails by means of contactors I and 8. These two secondariesare reversely connected across the rails so that at any given instantthe potential applied across the rails by secondary 4 is opposite inpolarity to the potential applied across the rails by secondary 5. Itfollows that the two secondaries 4 and 5 are included in series in thefollowing circuit: From the upper terminal of secondary 4, through aprimary winding I of a transformer- A3, shoe 6, rail l, shoe 1, primaryl3 of a transformer A2, secondary 5, primary ll of transformer A3, shoe8, rail I shoe 9, and primary l2 of transformer A2 to the lower terminalof secondary 4. At the instant that the upper terminal of secondary 4 ispositive, the direction of current flow in the different elements ofthis circuit is as indicated by the arrows shown in solid lines, fromwhich it will be seen that the fluxes due to currents in the primariesIll and H of transformer A3 aid each other in producing current insecondary 23, whereas the fluxes due to currents in the primaries l2 andI3 of transformer A2 oppose each other and so produce no current insecondary 22.

The secondary 23 of transformer A3 is connected with the input terminalsof a rectifier R3, and the output terminals of this rectifier areconnected with the operating winding of a direct current indicatingrelay F3. The secondary 22 of transformer A2 is connected with the inputterminals of a rectifier R2, and the output terminals of this rectifierare connected with the operating winding of another indicating relay F2.

The vehicle is provided with two indicating lamps LI and L2. The circuitfor lamp Ll passes from terminal E of a suitable source of current,through front contact l4 of relay F3 and lamp L1 to terminal 0 of thesame source of cur- 50 rent, so that this lamp is lighted whenever relayF3 is energized. The circuit for lamp L2 includes contact I4 of relay F3and contact I of relay F2 in series. The parts are so proportioned thatwhen the film between the contact shoes and 55 the rails is broken down,the voltage induced in secondary 23 of transformer A3 will besufficiently high to keep relay F3 energized, whereas when the film isnot broken down, so that current fails to flow in the circuit for thesecondaries of transformer Al, relay F3 will become deenergized and sowill open its contact l l. It follows that lamp LI will indicate whetheror not the output circuit of transformer Al is accomplishing itspurpose.

While the vehicle occupies section C-D, relay P is supposed to be open,and if it is open, alternating current from transformer Q will beapplied across the rails at the exit end of the section, and at theinstant when the upper rail I is positive, this current will flowthrough the secondaries of transformer AI and the primaries oftransformers A2 and A3 in the directions indicated by the dotted arrows.It will be seen from these arrows that the fluxes due to the trackwaycurrent in the primaries of transformer A3 oppose each other and so willcreate no potential in the secondary of this transformer. The fluxes dueto the trackway current in the primaries of transformer A2 assist eachother however, and so will induce alternating current in secondary 22 ofthis transformer, and this current will be sufiicient to energize relayF2. It follows that if the track relay is open and the track shuntingcircuit is functioning properly, lamp L2 will be lighted, whereas, ifthe track relay is not open, this lamp will be extinguished.

With the apparatus shown in Fig; 1, if the currents from transformer Alin the primaries i2 and is of transformer A2 should be unbalanced, it ispossible that relay F2 might be falsely energized by the resultant fluxcreated in the core of transformer A2. To avoid this, I preferably makethe frequency of the generator G on. the vehicle different from thefrequency of the trackway generator Q, and interpose means betweensecondary 22 and rectifier R2 to prevent the transmission to thisrectifier of current of the frequency of the vehicle-carried generatorG. Means of this nature are shown in Figs. 2 and 3.

Referring now to Fig. 2, a reactor 24 and a condenser 25 are connectedin series across theterminals of secondary 22 of transformer A2, and theinput terminals of rectifier R2 are connected across the condenser 25.The reactor 24 and condenser 25 aretuned to series resonance at thefrequency of the trackway source of current Q, so that when current ofthis frequency is induced in secondary 22, the potential acrosscondenser 25 will be high enough to effectively energize relay F2,whereas when potential of the frequency of generator G is induced inthis secondary the potential across condenser 25 will be so, low thatrelay F2 will not be effectively energized.

In Fig. 3, I have shown a filter interposed between transformer A2 andrelay F2 for transcondenser 3i interposed between condensers 29 and 21.The input terminals of rectifier R2 are connected across the outerterminals of reactor 28 and condenser 29. The reactor 26 and condenser27, and also the reactor 28 and condenser 29 are tuned to seriesresonance at the frequency of the generator G, thus providing two pathsof low impedance to shunt out the current from generator G but offeringpaths of high impedance to the current from the transformer Q. Thereactor 30 and condenser 3| are tuned to multiple resonance at thefrequency of the generator G, thus providing a path of high impedance tothe current from generator G but offering a path of low impedance to thecurrent from the transformer Q.

It is obvious, of course, that a combination of the tuned circuit shownin Fig. 2 and the filter circuit shown in Fig. 3 may be employed, ifdesired, to further sharpen the response of relay F2 to current of thetrackway frequency.

If desired, a manually operable switch N may be provided to shunt thesecondary 22 of transformer A2 when an indication of trackway conditionsis not desired.

Although I have herein shown and described only a few forms ofapparatus'embodying my invention, it is understood that various changesand modifications may be made therein within the scope of the appendedclaims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. In combination, a section of railway track provided with a trackcircuit including a normally closed track relay, means operating whenand only when said relay is open to supply alternating current from atrackway source across the rails of said section, a rail vehicle adaptedfor travel on said track, a transformer on said vehicle having a primarysupplied with alternating current and two secondaries each connectedacross the rails of the track in such manner that the instantaneousrelative polarities of such connections are opposite and the points ofconnection with each rail being spaced longitudinally so that the twosecondaries are in series in a circuit which includes a portion of eachrail, a second transformer on said vehicle having two primaries eachincluded in the connection between one of said secondaries and a trackrail and so wound that the currents flowing therein from saidsecondaries produce opposing fluxes whereby the currents which flow insaid primaries from said trackway source-produce aiding fluxes, andindicating means receiving energy from the secondary of said secondtransformer.

2. In combination, a section of railway track provided with a trackcircuit including a normally closed track relay, means operating whenand only when said relay is open to supply alternating current from atrackway source across the rails of said section, a rail vehicle adaptedfor travel on said track, a transformer on said vehicle having a primarysupplied with alternating current and two secondaries each connectedacross the rails of the track in such manner that the instantaneousrelative polarities of such connections are opposite and the points ofconnection with each rail being spaced longitudinally so that the twosecondaries are in series in a circuit which includes a portion of eachrail, a second transformer on said vehicle having two primaries eachincluded in the connection between one of said secondaries and a trackrail and so wound that the currents flowing therein from saidsecondaries produce opposing fluxes whereby the currents which flow insaid primaries from said trackway source produce aiding fluxes, arectifier having its input terminals connected with the secondary ofsaid second transformer, a direct current relay connected with theoutput terminals of said rectifier, and an indicator controlled by saiddirect current relay.

3. In combination, a section of railway track provided with a trackcircuit including a normally closed track relay, m'eans operating when.and only when said relay is open to supply alternating current from atrackway source of one frequency across the rails of said section, arail vehicle adapted for travel through said section, a transformer onsaid vehicle having a primary supplied with alternating current of adifferent frequency, said vehicle carried transformer having twosecondaries reversely connected across the rails of the track with thepoints of connection with each rail spaced longitudinally so that thetwosecondaries are in series in a circuit which includes a portion ofeach rail, a second transformer on said vehicle having two primarieseach included in the connection between one of said secondaries and atrack rail and so wound that the currents flowing therein from saidsecondaries produce opposing fluxes whereby the currents which flow insaid primaries from said trackway source produce aiding fluxes,indicating means receiving energy from the secondary of said secondtransformer, and means interposed between the secondary of said secondtransformer and said indicating means for preventing the indicatingmeans from being effectively energized by current of the vehicle-carriedfrequency in the event of unbalance of the currents from said firsttransformer in the primaries of the second transformer.

t. In combination, a section of railway track provided with a trackcircuit including a normally closed track relay, means operating whenand only when said relay is open to supply alternating current from atrackway source of one frequency across the rails of said section, arail vehicle adapted for travel through said section, a transformer onsaid vehicle having a primary supplied with alternating current of adifferent frequency, said vehicle carried transformer having twosecondaries reversely connected across the rails of the track with thepoints of connection with each rail spaced longitudinally so that thetwo secondaries are in series in a circuit which includes a portion ofeach rail, a second transformer on said vehicle having two primarieseach included in the connection between one of said secondaries and atrack rail and so wound that the currents flowing therein from saidsecondaries produce opposing fluxes whereby the currents which flow insaid primaries from: said trackway source produce aiding fluxes, arectifier having its input terminals connected with the secondary ofsaid second transformer, a direct current relay connected with theoutput terminals of said rectifier, and an indicator controlled by saiddirect current relay.

5. In combination, a section of railway track provided with a trackcircuit including a normally closed track relay, means operating whenand only when said relay is open to supply alternating current from atrackway source of one frequency across the rails of said section, arail vehicle adapted for travel through said section, a transformer onsaid vehicle having a primary supplied with alternating current of adifferent frequency, said vehicle carried transformer hav ing twosecondaries reversely connected across the rails of the track with thepoints of connection with each rail spaced longitudinally so that thetwo secondaries are in series in a circuit which includes a portion ofeach rail, a second transformer on said vehicle having two primarieseach included in the connection between one of said secondaries and atrack rail and so wound that the currents flowing therein from saidsecondaries produce opposing fluxes whereby the currents which flow insaid primaries from said trackway source produce aiding fluxes, areactor and a condenser connected' in series across the secondary ofsaid second transformer and tuned to resonance at the frequency of saidtrackway source, and indicating means controlled by the voltage acrosssaid condensers.

6. In combination, a section of railway track provided with a trackcircuit including a normally closed track relay, means operating whenand only when said relay is open to supply alternating current from atrackway source of one frequency across the rails of said section, arail g vehicle adapted for travel through said section, a transformer onsaid vehicle havinga primary supplied with alternating current of adifierent frequency, said vehicle carried transformer having twosecondaries reversely connected across the rails of the track with thepoints of connection with each rail spaced longitudinally so that thetwo secondaries are in series in a circuit which includes a portion ofeach rail, 2. second transformer on said vehicle having two primarieseach included in the connection between one of said secondaries and atrack rail and so wound that the currents flowing therein from saidsecondaries produce opposing fluxes whereby the currents which flow insaid primaries from said trackway source produce aiding fluxes,indicating means receiving energy from the secondary of said secondtransformer, and a filter interposed between the secondary of saidsecond transformer and said indicating means and tuned to pass currentof the frequency of said trackway source but not of said vehicle carriedsource.

'7. In combination, a section of railway track provided with a trackcircuit including a normally closed track relay, means operating whenand only when said relay is open to supply alternating current from atrackway source across the rails of said section, a rail vehicle adaptedfor travel through said section, a transformer on said vehicle having aprimary supplied with alternating current and two secondaries reverselyconnected across the rails of the track with the points of connectionwith each rail spaced longitudinally so that the two secondaries are inseries in a circuit which includes a portion of each rail, a secondtransformer on said vehicle having two primaries each included in theconnection between one of said secondaries and a track rail and so woundthat the currents flowing therein from said secondaries produce opposingfluxes whereby the currents which flow in said primaries from saidtrackway source produce aiding fluxes, a third transformer on saidvehicle having two primaries each included in the connection between oneof said secondaries and a track rail and so wound that the currentsflowing therein from said secondaries produce aiding fluxes whereby thecurrents which flow .in the primaries of said third ransformer from saidtrackway source produce opposing fluxes, a rectifier having its inputterminals connected with the secondary of said second transformer, adirect current relay connected with the output terminals of saidrectifier, a second rectifier connected with the secondary of said thirdtransformer, a second relay connected with the output terminals of saidsecond rectifier, an indicating lamp controlled by a front contact ofsaid second direct current relay, and a second indicating lampcontrolled by a front contact of said first direct current relay and afront contact of said second-direct current relay.

8. In combination, a section of railway track provided with a trackcircuit including a normally closed track relay, means operating whenand only when said relay is open to supply alternating current from atrackway source across the rails of said section, a rail vehicle adaptedfor travel through said section, a transformer on said vehicle having aprimary supplied with alternating current and two secondaries reverselyconnected across the rails of the track with the points of connectionwith-each rail spaced longitudinally so that the two secondaries are inseries in a circuit which includes a portion of each rail, a secondtransformer on said vehicle having two primaries each included in theconnection between one of said secondaries and a track rail and so woundthat the currents flowing therein from said secondaries produce opposingfluxeswhereby the currents which flow in said primaries from saidtrackway source produce aiding fluxes, a third transformer on saidvehicle having two primaries each included in the connection between oneof said secondaries and a track rail and so wound that the currentsflowing therein from said secondaries produce aiding fluxes whereby thecurrents which flow in the primaries of said third transformer from saidtrackway source pro duce opposing fluxes, and indicating meanscontrolled jointly by the secondaries of said second and thirdtransformers.

' 9. In combination, a section of railway track provided with a trackcircuit including a normally'closed track relay, means operating whenand only when said relay is open to supply alternating current from atrackway source across the rails of said section, a rail vehicle adaptedfor travel through said section, a transformer on said vehicle having aprimary supplied with alternating current and two secondaries reverselyconnected across the rails of the track with the points of connectionwith each rail spaced longitudinally so that the two secondaries are inseries in a circuit which includes a. portion of each rail, a secondtransformer on said vehicle having two primaries each included in theconnection between one of said' secondaries and a track rail and sowound that the currents flowing therein from said secondaries produceopposing fluxes whereby'the currents which flow in said primaries fromsaid trackway source produce aiding fluxes, a third transformer on saidvehicle having two primaries each included in the connection between oneof said secondaries and a track rail and so wound that the currentsflowing therein from said secondaries produce aiding fluxes whereby thecurrents which flow in the primaries of said third transformer from saidtrackway source produce opposing fluxes, a first indicating relaysupplied with energy from the secondary of said second transformer, asecond indicating relay supplied with energy from the secondary of saidthird transformer, a first lamp lighted when and only when said thirdindicating relay is energized, and a second lamp lighted when and onlywhen both of said indicating relays are energized.

10. In combination, a section of railway track provided with a trackcircuit including a normally closed track relay, means operating whenand only when said relay is open to supply alterhating current from atrackway source across the rails of said section, a rail vehicle adaptedfor travel through said section, a transformer on said vehicle having aprimary supplied with alternating current differing from said trackwaysource in frequency, said transformer having two secondaries reverselyconnected across the rails of the track with the points of connectionwith each rail spaced longitudinally so that the two secondaries are inseries in av circuit which includes a portion of each rail, a secondtrans former on said vehicle having two primaries each included in theconnection between one of said secondaries and a track rail and so woundthat the currents flowing therein from said secondaries produce opposingfluxes whereby the currents which flow in said primaries from saidtrackway source produce aiding fluxes, a third transformer on saidvehicle having two primaries each included in the connection between oneof said secondaries and a track rail and so wound that the currentsflowing therein from said sec ondaries produce aiding fluxes whereby thecurrents which flow in the primaries of said third transformer from saidtrackway source produce opposing fluxes, a rectifier having its inputterminals connected with the secondary of said second transformer, adirect current relay connected with the output terminals of saidrectifier, a second rectifier connected with the secondary of said thirdtransformer, a second relay connected with the output terminals of saidsecond rectifier, an indicating lamp controlled by a front contact ofsaid second direct current relay, a. second indicating lamp controlledby afront contact of said first direct current relay and a front contactof said second direct current relay,

and means interposed between the secondary of said second transformerand said first direct current relay for preventing such relay from beingeffectively energized by current of said vehicle carried frequency inthe event of unbalance of the currents from said first transformer inthe primaries of the second transformer.

11. In combination, a section of railway track provided with a trackcircuit including a normally closed track relay, means operating whenand only when said relay is open to supply alternating current from atrackway source across the rails of said section, a rail vehicle adaptedfor travel through said section, a transformer on said vehicle having aprimary supplied with alternating current diflering from said trackwaysource in frequency, said transformer having two secondaries reverselyconnected across the rails of the track with the points of connectionwith each rail spaced longitudinally so that the two secondaries are inseries in a circuit which includes a portion of each rail, a secondtransformer on said vehicle having two primaries each included in theconnection between one of said secondaries and a track rail and so woundthat the currents flowing therein from said secondaries produce opposingfluxes whereby the currents which flow in said primaries from saidtrackway source produce aiding fluxes, a third transformer on saidvehicle having two primaries each included. in the connection between.one of said secondaries and a track rail and so wound that the currentsflowing therein from said secondaries produce aiding fluxes whereby thecurrents which flow in the primaries of said third transformer from saidtrackway source produce opposing fluxes, indicating means controlledjointly by the secondaries of said second and third transformers, andtuning means interposed between the secondary of said second transformerand said indicating means for preventing false operation of saidindicating means by current of the frequency of said vehicle carriedsource.

12. In combination, a section of railway track provided with a trackcircuit including a normally closed track relay, means operating whenand only when said relay is open to supply alternating current from atrackway source across the rails of said section, a rail vehicle adaptedfor travel on said track, a circuit on said vehicle connected across therails and including a source of current on said vehicle for supplyingenergy to the rails for breaking down the resistance of the rail surfaceto aid the shunting of said track relay while the vehicle occupies saidsection, and means on said vehicle including at least a portion of saidvehicle carried circuit and responsive to current from said trackwaysource for indicating that said track relay is open.

13. In combination, a section of railway track provided with a trackcircuit including a normally closed track relay, a rail vehicle fortravel through said section, means including a source of current on saidvehicle for supplying energy to the track rails to break down theresistance film of the rail surface and to shunt said track relay, andmeans including a trackway source of current and at least a portion ofsaid vehicle carried means and operating while the vehicle occupies saidsection to indicate on the vehicle whether or not said track relay isopen.

14. In combination, a section of railway track provided with a trackcircuit including 9. normally closed track relay, a rail vehicle fortravel through said section, means including a source of current on saidvehicle for supplying energy to the track rails to break down theresistance film of the rail surface and to shunt said track relay, andmeans including at least a portion of said vehicle carried means andoperating While the vehicle occupies said section to indicate on thevehicle whether or not said track relay is open.

15. In combination, a section of railway track provided with a trackcircuit including a first trackway source of current and a track relay,a rail vehicle for travel through said section, a track shunting circuiton the vehicle exclusive of the wheels and axles thereof for providing alow impedance path from one to the other rail for causing a response ofsaid track relay when said vehicle occupies said section, and meanscontrolled by said track relay and including a second trackway source ofcurrent and at least a portion of said track shunting circuit forindieating on the vehicle Whether or not said track relay has responded.

16. In combination, a section of railway track provided with a trackcircuit including a first trackway source of current and a track relay,a

rail vehicle for travel through said section, a track shunting circuiton the vehicle exclusive of the wheels and axles thereof for providing alow impedance path from one to the other rail for causing a response ofsaid track relay when said vehicle occupies said section, and meanseffective when said vehicle occupies said section and including a secondtrackway source of current and at least a portion of said track shuntingcircuit for indicating on the vehicle whether or not said track relayhas responded.

17. In combination, a section of railway track provided with a trackcircuit including a first trackway source of current and a track relay,a rail vehicle for travel through said section, a circuit on the vehicleexclusive of the wheels and axles thereof for shunting said track tocause a response of said track relay when said vehicle occupies saidsection, and means including a second trackway source of current forcausing a current to how in at least a portion of said circuit, saidcurrent being used to provide an indication as to whether or not saidtrack relay has responded.

18. In combination, a section of railway track, a relay and a firsttrackway source of current each connected across the rails of saidsection, a rail vehicle for travel through said section, a circuit onthe vehicle exclusive of the wheels and axles thereof and extending fromone to the other rail of said track and effective for causing a responseof said relay when said vehicle occupies said section, and meanscontrolled by said relay and including a second trackway source ofcurrent and at least a portion of said circuit for indicating on thevehicle whether or not said relay has responded.

19. In combination, a section of railway track,

a relay and a first trackway source of current each connected across therails of said section, a rail vehicle for travel through said section, acircuit on the vehicle exclusive of the wheels and axles thereof andextending from one to the other rail of said track and effective forcausing a response of said relay when said vehicle occupies saidsection, and means effective when said vehicle occupies said section andincluding a second trackway source of current and at least a portion ofsaid circuit for indicating on the vehicle whether or not said relay hasresponded.

20. In combination with a section of railway track and a rail vehiclethereon, a track relay and a first trackway source of current eachconnected across the rails of said section, a circuit on the vehicleextending from one to the other rail of said track and effective forcausing a response of said track relay when the vehicle occupies saidsection, and means including a second trackway source of current and atleast a portion of said circuit for indicating on the vehicle whether ornot said relay has responded.

BERNARD E. OI-IAGAN.

